Transfer of images to fabric is of interest to consumers wishing to personalize clothing, mouse pads, decorative items et cetera. While methods for transferring graphical illustrations and photographic images are well described in the art, many of these means are not suitable for home use. For example, fabric may be printed directly using inkjet printers containing inks which comprise dyes capable of reacting with fabric fibers, but these methods are limited in that complex shapes such as t-shirts and the like are difficult or impossible to feed through an inkjet printer designed for home use.
Therefore, methods have been developed which make use of transfer inks or transfer media. For example, an ink containing a dye which is mobile when heated (preferably ironed) can be loaded into an inkjet printer (U.S. Pat. No. 5,488,907 to Sawgrass Systems) or used to make transfer ribbons in a thermal printer (U.S. Pat. No. 5,522,317 to Sawgrass Systems). The image of interest is printed on, for example, clay-coated paper. The coated paper is held in contact with the fabric which is to receive the image and with thermal activation (ironing or a heat press) the dyes are transported into the fabric. Such a method is limited, however, to relatively expensive thermal printers not typically found in homes, or to specific inkjet printers in which ink is ejected by piezoelectric pulses. Such a heat activated ink cannot be successfully employed in the more ubiquitous thermal inkjet printers in which ink must be heated in order to be ejected. In addition, these methods result in reduced optical density of the images since the dye is never fully transferred to the fabric, and the dye that is transferred sinks into the fabric. Furthermore, for the dyes to sublime, temperatures in excess of the softening point of preferred fabrics such as polyester and nylon are exceeded. Constraints on allowable dwell time at the subliming temperature require the consumer to exercise caution so that the fabric is not damaged.
Methods in which the entire printed image (inks or dyes and the ink or dye receptive layer) are transferred to fabric have also been developed for inkjet printers. Such methods have the advantage that many of the commercially available inkjet printers may be used to generate the image. However, some obstacles still exist in perfecting this transfer method. In U.S. Pat. No. 4,980,224 to Foto-Wear, Inc., an ink receptive coating comprising Singapore Dammar resin mixed with abrasive particle is described. A natural resin such as Singapore Dammar resin does not exhibit high swellability in aqueous inks like those used in home inkjet printers. As a result, such a coating will not function as an efficient inkjet receptive layer for the high ink laydowns required for high quality graphic or photographic images. Coalescence or pooling of the ink may occur before the image has a chance to completely dry, causing poor image quality. Further, such a receptive layer requires a heat press rather than an iron for best transfer results, which is not typically available in the home. An attempt is made to address such concerns in U.S. Pat. No. 5,501,902 to Kimberly Clark. In this case, the ink receptive element is designed so that it can be efficiently transferred by conventional ironing. However, it too comprises hydrophobic particulate species. As a result, high quality images with heavy ink laydowns often exhibit unacceptable bleed when printed on such materials. Moreover, such an inkjet printable material also requires high (about 170.degree. C.) temperatures for effective transfer to fabric, causing the same concerns for fabric damage described above. Moreover, the preferred embodiments of such a transfer material involve deposition of several layers of ink absorbing materials, raising the manufacturing cost and complexity of producing such items.